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arXiv · 2405.08476

Cosmological constraints on mass-varying dark matter

Amlan Chakraborty·Anirban Das·Subinoy Das·Shiv K. Sethi
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Abstract

As one of the fundamental unknowns of our Universe, the mass of dark matter remains to be a topic of great interest. We consider the possibility of a time-variation of the dark matter mass. We study the cosmological constraints on a model where the dark matter mass transitions from zero to a finite value in the early Universe. In this model, the matter power spectrum exhibits power suppression below a certain scale that depends on the epoch of transition, and the angular power spectrum of the cosmic microwave background shows a distinctive phase shift and power suppression at small scales. We use the latest cosmic microwave background data and the $S_8$ priors from weak lensing data to place a lower limit on the transition redshift. We also find that the data from the ACT show a mild preference for the mass-varying dark matter model over $\Lambda$CDM.

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Amlan Chakraborty, Anirban Das, Subinoy Das, Shiv K. Sethi. 2024-05-14. Cosmological constraints on mass-varying dark matter. https://doi.org/10.1103/physrevd.111.063515

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